Hello! First off, welcome to YT! I also wanted to say that I think your name for your yorkie is absolutely clever and adorable!
I love it!
Anyway, do you keep him in a little pen or crate, or does he get to have free run of the house sometimes? I have this thing that if I cannot keep a close eye on my Luigi, then he stays in his crate or his pen (with peepads in the area) so that there are no accidents around the house. Otherwise, he may start to get the idea that it's okay to go elsewhere.
And the fact that there are other dogs may be a reason, he could be marking territory, but I suggest if he's ever around the house, that someone keeps a careful eye on him to prevent accidents and bring him to the right potty area. Otherwise, he should be in a pen or crate.
As for ripping up paper, I bought this tray from Petco that snaps paper in place. It works really well. Sometimes Luigi manages to get the paper out when I go to work for a long time (I guess he gets bored), but for the most part, it works really really well. And the pee/poop doesn't seep any residue through the paper onto your actual floor, so clean up is a little easier. I've seen it come in pink or blue. You can do a search for it at Petco
Hope this helps a little. Good luck!